Lignin-Based Additives for Improved Thermo-Oxidative Stability of Biolubricants

There is an environmental concern regarding the use of petroleum-based lubricants, which are generally toxic and nonbiodegradable. Biobased such as vegetable oils, alternative: they show excellent lubricity, readily biodegradable nontoxic. However, a major disadvantage using oils in lubricant applications their lack thermo-oxidative stability, can be improved by antioxidant additives. Here, we propose lignin-based additives biolubricant formulations to improve this feature, based on lignin’s known properties. To ensure stable dispersion oil, lignin was partially esterified. Antioxidant properties before after palmitoylation were demonstrated 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. Four different fractions, commercial Protobind P1000 soda from straw, solvolytically fractionated two fractions reductively catalyzed fractionation (RCF) native birch wood, tested with castor oil base oil. Those exhibited performance compared butylated hydroxytoluene (BHT), commonly used antioxidant. Formulations modified possess illustrated increased oxidation induction time. Additionally, rheological tribological tests demonstrate similar, or some cases improved, lubricating This study showcases successful incorporation antioxidants formulations, tackling environment-friendly lubricants.